To embed google maps, you'll need to go to the google map website and follow these instructions to get the Embed code.
Click on the cog wheel icon (bottom right) and select 'Share and Embed Map' - then select Embed Map.
A popup window will appear with some code in that looks something like this:
<iframe src="https://www.google.com/maps/embed?pb=!1m5!3m3!1m2!1s0x487e70cdd52e6183%3A0xc145eb01850cc77d!2sNewcastle+University!5e0!3m2!1sen!2s!4v1390319056933" width="600" height="450" frameborder="0" style="border:0"></iframe>
Select the code and copy using "Control+C".
Return to the All Purpose Content, and click on the HTML button in the second tier of formatting controls (sixth from the right).
A popup window will appear with the HTML code for the page you're working on.
Paste the code into that window using "Control+V"